In a chain and sprocket transmission, wear of the sprocket includes wearing of the valley between teeth in a radial direction, so that the pitch of the sprocket teeth decreases. As the chain wears, the individual links may stretch and the bearings between the links wear, all of which increases the pitch of the chain. As the wear of the sprocket and the chain increases, this causes a corresponding increase in the rate of wear. For example, a sprocket after being in use for 1,000 hours may have four times the wear as it had after 500 hours of use.